How Can I use parameter in OPENROWSET() function? - sql-server

Question

I am trying to get an image from a shared folder, but while I am trying to pass parameter in OPENROWSET function I am getting an error:
Incorrect Syntax near......
I tried this one so far:
alter FUNCTION dbo.GetImage (#imagePath varchar(200))
RETURNS varbinary(max)
AS
BEGIN
DECLARE #Result varbinary(max);
EXEC master..xp_cmdshell 'net use Z: \\192.168.1.175\Rack /user:192......\username pass';
SELECT #Result = ProjectImage
FROM OPENROWSET(BULK 'Z:' + #imagePath, SINGLE_BLOB) AS ProjectImage(ProjectImage);
RETURN #Result;
END;

Answer 1

The short answer is you can't. OPENROWSET only takes a string constant, so you need to use dynamic SQL to inject your file path to the SQL then execute that SQL. You will however not be able to do this within a function, so you're best bet is to use a stored procedure and an output parameter to get the varbinary out:
CREATE PROCEDURE dbo.GetImage (#imagePath varchar(200), #Result VARBINARY(max) OUTPUT)
AS
BEGIN
EXEC master..xp_cmdshell 'net use Z: \\192.168.1.175\Rack /user:192......\username pass';
DECLARE #SQL nvarchar(max) =
N'SELECT #Result = BulkColumn
FROM OPENROWSET(BULK ''Z:' + #imagePath + N''', SINGLE_BLOB) AS t';
EXECUTE sp_executesql #SQL, N'#Result varbinary(max) OUTPUT', #Result OUTPUT;
RETURN #Result;
END;
With that being said, if you're only looking to read a file and convert it to binary then SQL doesn't really feel like the right tool for the job - I'm never a big fan of conflating file system tasks with the database except for in ad hoc processes, but ad hoc processes should not require a permanent solution like a function or a stored procedure.